Top Prospect Promotions: Choice, Castellanos

As we learn of top prospect promotions over September, we'll try to keep tabs on them in a daily basis. Here are Sunday's promotions:

The Athletics are set to bring up outfielder Michael Choice, the San Francisco Chronicle's Susan Slusser first reported last night. Choice entered the season as the A's second overall prospect as rated by Baseball America, which praised his strength and bat speed. He currently sits as the 92nd overall prospect in the game on Mayo's list. The 23-year-old has delivered a .302/.390/.445 line and fourteen homers in 600 plate appearances over his first season at Triple-A.

The Tigers have officially called up the team's top prospect, with the team announcing on Twitter that it has purchased the contract of outfielder Nick Castellanos. The former third baseman entered the year as a consensus top-50 prospect in all of baseball, and moved up to 11th overall in the mid-season ranking of MLB.com's Jonathan Mayo. As Mayo explained, the 21-year-old hits the ball to all fields and has solid pop.